Projection type liquid crystal display device

ABSTRACT

A projection type liquid crystal display device using liquid crystal display elements, which has a light source; illumination optics having a function of irradiating a plane to be irradiated with light emitted by the light source; and liquid crystal display elements modulating light; projection optics for projecting light exiting from the liquid crystal display elements; wherein the illumination optics include at least an elliptic mirror and a spherical mirror, and the illumination optics include further a first lens array and a second lens array, in which a plurality of lenses are arranged perpendicularly to an optical axis, from the light source side; and a condenser lens for irradiating the liquid crystal display elements with light after exit from the second lens array with a high efficiency. In this way it is possible to realize a bright projection type liquid crystal display device having a small size and a good image quality performance.

BACKGROUND OF THE INVENTION

The present Invention relates to a projection type liquid crystaldisplay device using liquid crystal display elements, and in particularto a projection type liquid crystal display device having a small sizeand a good image quality performance such as brightness, etc.

Heretofore, as an image display device, there is known a projection typedisplay device, in which an optical image formed on light valves asvariations in optical characteristics, depending on image signals, isilluminated by means of illumination optics to be enlarged and projectedon a screen by means of projection optics. A number of projection typeliquid crystal display devices have been proposed, each of which usesliquid crystal display elements as light valves for such a displaydevice. A twisted nematic (TN) type liquid crystal display element,which is a representative example of a liquid crystal display element,is so constructed that two polarizers are disposed before and after aliquid crystal cell, in which liquid crystal is injected between a pairof transparent base plates, each of which has a transparent electrodefilm, so that polarization directions thereof differ by 90° from eachother and a number of such liquid crystal display elements are arrangedso that light intensity of incident light transmitted by each of them iscontrolled by combining an action to rotate a polarization plane by anelectro-optical effect of the liquid crystal with an action to select apolarization component by one of the polarizers to display imageinformation. Recently performance such as resolution, etc. is rapidlyimproved as down-sizing of such transmission type or reflection typeliquid crystal display elements themselves is advanced so thatdown-sizing and improvement in performance of a display device usingsuch liquid crystal display elements are advanced. In this way,projection type liquid crystal display devices have been newly proposednot only for conventional image display using video signals, etc. butalso for image output devices of personal computers.

However a prior art projection type liquid crystal display device hadproblems that it has a large size and that performance such asbrightness of image, etc. finally obtained is insufficient. Althoughdown-sizing of light valves, i.e. liquid crystal display elementsthemselves, is efficient for down-sizing of a whole display device,since an area illuminated by illumination optics is decreased, when thesize of liquid crystal display elements is decreased, problems takeplace that a ratio of a light flux projected on liquid crystal displayelements to a whole light flux emitted by a light source (hereinbelowcalled light utilization efficiency) is lowered, etc. As the result, itwas difficult to realize down-sizing of the whole device and improvementof performance such as brightness, etc. at the same time. Further, incase of a projection type liquid crystal display device, since variousfactors such as optical characteristics of a projection lens, opticalcharacteristics of liquid crystal display elements, etc. apart from theillumination optics have influences on image quality performance, it wasdifficult to obtain a display device having a small size and a goodimage quality performance, if only the illumination optics wereimproved.

SUMMARY OF THE INVENTION

A main object of the present invention is to provide a projection typeliquid crystal display device having a small size and a good imagequality performance.

Another object of the present invention is to raise utilizationefficiency of light emitted from a light source.

Still another object of the present invention is to make brightnessuniform over a whole screen.

According to the present invention, a projection type liquid crystaldisplay device, which includes a light source; illumination opticshaving an action to irradiate a surface to be irradiated with lightemitted by the light source; liquid crystal display elements modulatinglight; and projection optics for projecting light emitted by the liquidcrystal display elements, is so constructed that the illumination opticshave at least one elliptic mirror and one spherical mirror and that theillumination optics comprise further a first lens array and a secondlens array, in which a plurality of lenses are arranged perpendicularlyto an optical axis from the light source side, and a condenser lens forirradiating the liquid crystal display elements with light, which hasbeen emitted by the second lens array, with a high efficiency.

In this way, it is possible to realize a bright projection type liquidcrystal display device having a small size and a good image qualityperformance by raising utilization efficiency of light emitted by thelight source.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will now be described inconjunction with the accompanying drawings, in which;

FIG. 1 is a diagram showing the construction of an optical system in aprojection type liquid crystal display device according to the presentinvention;

FIG. 2 is a cross-sectional diagram showing the principle of an actionof a part of illumination optics in FIG. 1;

FIG. 3 is a diagram showing the construction of an embodiment of a lightsource used in FIG. 1;

FIG. 4 is a cross-sectional diagram showing the principle ofillumination optics used in FIG. 1;

FIG. 5 is a cross-sectional view and a side view showing a n example ofthe shape of a first lens array used in FIG. 1;

FIG. 6 is a cross-section al view and a side view showing an example ofthe shape of a second lens array used in FIG. 1;

FIG. 7 is a diagram showing the construction of an embodiment of aprojection type liquid crystal display device according to the presentinvention;

FIG. 8 is a diagram showing the construction of a concrete example ofillumination optics used in the projection type liquid crystal displaydevice according to the present invention; and

FIG. 9 is a diagram showing another embodiment of a condenser lens inFIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Several embodiments of the present invention will be explained below,referring the drawings.

FIG. 1 is a diagram showing the construction of an optical system in aprojection type liquid crystal display device according to the presentinvention. In FIG. 1, a light source 1 is an incandescent larp such as ametal halide lamp, xenon lamp, halogen lamp, etc. In illumination opticsconsisting of the light source 1, an elliptic mirror 5 and a sphericalmirror 6, light emitted by the light source 1 is reflected by theelliptic mirror 5 and the spherical mirror 6. After having passedthrough a first lens array 22, it passes through a second lens array 23and enters a condenser lens 7. The condenser lens 7 has a positivereflective power and an action to focus further light emitted by theillumination optics 2. Light, which has passed through the condenserlens 7, irradiates liquid crystal display elements 3. Light, which haspassed through the liquid crystal display elements 3, enters a fieldlens 8 having an action to have the light enter projection optics 4,which are e.g. a zoom lens. Thereafter it passes through the projectionoptics 4 to reach a screen 9. An image formed on the liquid crystaldisplay elements 3 by the field lens 8 and the projection optics 4 isenlarged to be projected on the screen 9. Thus the whole devicefunctions as a display device.

Next functions of principal parts of the projection type liquid crystaldisplay device according to the present invention will be explained indetail. FIG. 2 is a cross-sectional diagram showing the principle of anaction of a part of illumination optics in the projection type liquidcrystal display device according to the present invention, which showsan aspect, in which light emitted by the light source is reflected bythe elliptic mirror 5 and the spherical mirror 6.

A point P and another point P′ indicated in FIG. 2 indicate positions ofthe first and the second focal point, respectively, of an ellipticsurface, which is a reflecting surface of the elliptic mirror. Light B1exiting from the point P towards the elliptic mirror 5 is reflected bythe elliptic mirror 5 and arrives at the point P′ on an optical axis 18.Consequently all the light exiting from the point P and reflecteddirectly by the elliptic mirror 5 reaches the point P′. On the otherhand, in case where the center of a spherical surface, which is areflecting surface of the spherical mirror, is in accordance with thepoint P, light B2 exiting from the position of the point P towards thespherical mirror 6 is reflected by the spherical mirror 6 to returnagain to the point P and to proceed to the elliptic mirror 5 and reachesthe point P′ after having been reflected by the elliptic mirror 5. Bythese actions, in the light exiting from the position of the point P, inprinciple all the light entering the elliptic mirror 5 or the sphericalmirror 6 reaches the point P′. The light B2 is light, which didn't reachheretofore the surface to be irradiated such as liquid crystal displayelements, and therefore it is possible to raise the light utilizationefficiency by arranging the liquid crystal display elements in theneighborhood of the point P′ in the construction indicated in FIG. 2.Further, if it is tried to raise the light utilization efficiency byusing only one reflecting mirror such as the elliptic mirror 5 withoutspherical mirror 6 as in prior art illumination optics, problems areproduced that the size of reflecting mirror is increased or that aprojection lens having a small F number as projecting means is required,accompanied therewith, which enlarges the size of the projection lens.

FIG. 3 is a diagram showing the construction of an example of the lightsource 1 in the projection type liquid crystal display device accordingto the present invention, which is a construction where the light sourceconsists in a lamp 10.

In FIG. 3, reference numeral 13 is a light emitting bulb made of quartzglass, etc., in which gas is enclosed for having it act as a device forigniting a metal vapor discharge bulb including mercury, argon, etc. InFIG. 3, reference numeral 11 is an electrode; 12 is a reflective layer;15 is a molybdenum foil having functions to maintain air-tightness ofthe light emitting bulb 13, etc.; 14 is lead wire; and 16 is a base.Light is emitted from a lighting point 17 by discharge between a pair ofelectrodes 11. Here the reflective layer 12 is made of zirconia, etc.and has functions to maintain temperature of the light emitting bulb, toincrease vapor pressure, etc., which gives rise to an effect that asatisfactory continuous light emitting property or a long life time oflamp can be obtained. However, since in the light emitted by thelighting point 17 light entering the reflective layer 12 was absorbed ordiffused and reflected, illumination optics using a prior art lamp, inwhich the reflective layer was applied over a wide region, had a badlight utilization efficiency. In case where a lamp having theconstruction indicated in FIG. 3 according to the present invention isused, the reflective layer 12 is disposed only in a region in accordancewith the shape of the spherical mirror. That is, the shape of thereflective layer is so determined that the light B emitted by thelighting point 17 indicated in FIG. 3 enters the spherical mirror 6indicated in FIG. 2 without being absorbed or reflected by thereflective layer 12. In this way, by using illumination opticsconsisting of the lamp 10 and the construction indicated in FIG. 2 incombination, it is possible to use light, which was heretofore absorbedor diffused and reflected by the reflective layer 12, for irradiationwith a high efficiency, which raises the light utilization efficiency.On the other hand, in case where a lamp is disposed so that the lightingpoint 17 is positioned in the neighborhood of the point P in FIG. 2, asdescribed above, light emitted by the lighting point 17 and entering thespherical mirror 6 is reflected to return again towards the lightingpoint. For this reason, light reflected by the spherical mirror 6 isprojected to the light emitting bulb 13 in the lamp, which has effectsthat the temperature of the light emitting bulb is maintained, that thevapor pressure is raised, etc. That is, the spherical mirror 6 has afunction identical to that of the prior art reflective layer.Consequently it is possible to obtain illumination optics having a highlight utilization efficiency by combining the the reflecting mirrorconstruction indicated in FIG. 2 with the lamp indicated in FIG. 3,owing to mutual reactions thereof, without worsening the light emittingproperty, the life time, etc. of the lamp, even if the area where thereflective layer is applied is decreased.

In addition, in the construction according to the present invention, incase where the efficiency to return light from the spherical mirror 6 tothe lamp is high and further a satisfactory light emitting performance,a long life time, etc. can be obtained, the reflective layer 12 may beomitted. In order to have the spherical mirror 6 have satisfactorily thefunction of the prior art reflective layer 12, it is preferable to forma reflecting film on the reflecting surface of the spherical mirror 6 byaluminium evaporation, etc. rather than to construct it by a dichroicmirror which reflects only visible light.

Next functions of the first and the second lens array according to thepresent invention will be explained, referring to FIG. 4.

FIG. 4 is a cross-sectional view showing the principle of the action ofthe lens arrays in the illumination optics according to the presentinvention.

In the illumination optics indicated in FIG. 4, light emitted from thelight source 1 enters the first lens array 22 to be focused on thesecond lens array 23. After having passed through the second lens array,it enters the condenser lens 7 to irradiate the liquid crystal displayelements 3. At that time, the first lens array 22 is so set that theimage of the lighting point of the light source 1 is focused at theposition of the second lens array 23. In this way, the light fluxpassing through the second lens array 23 is made narrow and as theresult the first lens array 22 has a function to increase the ratio ofthe amount of light passing through the second lens array 23.

Further the second lens array 23 has a same number of lenses (18 in theembodiment of the present invention) as the first lens array 22, eachlens of the former corresponding to the respective lens of the latter,and each lens of the second lens array 23 has a function to focus arectangular aperture figure of a corresponding lens of the first lensarray 22 on the liquid crystal display elements 3. As the result, theshape of light irradiating the liquid crystal display elements 3 isrectangular and it is possible to realize an image, which is bright inthe whole, and easy to see, in which brightness uniformity is high.

FIG. 5 shows an example of the shape of the first lens array 22according to the present invention.

As indicated in FIG. 5, the shape of each of the lenses constituting thefirst lens array 22 is rectangular and thus it is possible to irradiatethe liquid crystal display elements 3 with light spots, each of which isrectangular. Further, each of black points indicated in FIG. 5represents an optical axis of each of the lenses constituting the firstlens array 22. The position of the light focused on the second lensarray 23 by the first lens array 22 can be controlled by the fact thatthe optical axis of each lens is shifted from the geometrical center ofthe rectangular shape and in this way it is possible to increase theamount of light passing through the second lens array 23 whiledecreasing the size of the second lens array 23 by setting the opticalaxis at the optimum position.

FIG. 6 shows an example of the shape of the second lens array 23according to the present invention.

As indicated in FIG. 6, the second lens array 23 according to thepresent invention is constructed by lenses, each of which has anaperture figure quadrilateral or pentagonal. In case where a lamp asindicated in FIG. 3 is used as a light source, the cross section of thelighting point is usually approximately elliptic and as the result, theimage of the lighting point of the light source on the second lens array23 formed by the first lens array 22 is approximately elliptic. For thisreason, if the lenses constituting the second lens array 23 arerectangular, there exist many portions, for which light transmittance islow, i.e. dead spaces, which gives rise to a problem that the secondlens array 23 should be large or that light utilization efficiency islow. According to the present invention, owing to the fact that theaperture figure of the lenses of the second lens array 23 at least oneis quadrilateral and at least one is pentagonal, as indicated in FIG. 6,the dead spaces are decreased and illumination optics having a highlight utilization efficiency can be obtained while keeping the smallsize of the whole device.

Owing to the functions described above, by using small liquid crystaldisplay elements, it is possible to realize a bright liquid crystaldisplay device having an image, which is uniform over a whole screen,and a good image quality performance, even if the whole display deviceis small.

Next a concrete whole construction of the projection type liquid crystaldisplay device according to the present invention will be explained.

FIG. 7 is a diagram showing an embodiment of the projection type liquidcrystal display device according to the present invention.

The embodiment indicated in FIG. 7 shows a three plate projection typeliquid crystal display device using 3 plates in total, in whichtransmission type liquid crystal display elements acting as liquidcrystal light valves correspond to three colors, which are the threeprimary colors, i.e. R (red), G (green) and B (blue). In the presentembodiment, light emitted by a lamp 10 serving as the light source,which is e.g. a metal halide lamp, enters the first lens array 22 afterhaving been reflected by the elliptic mirror 5 or the spherical mirror6. Light, which has passed through the first lens array 22, passesthrough the second lens array 23. Thereafter light of G (green) and B(blue) is reflected by an R (red) transmission dichroic mirror arrangedat an angle 45° with respect to the optical axis and light of R (red) istransmitted therethrough. The optical path of a reflected R light beamis bent by a reflective mirror 29, passes through a condenser lens 7Rand an incident side polarizer 20R to enter liquid crystal displayelements 3R constructed by a counter-electrode, liquid crystals, etc.and passes through an exit side polarizer 21R and a field lens 8Rdisposed on the light exit side of the liquid crystal display elements3R. An R light beam exiting from the field lens 8R passes through adichroic mirror 26 having a function of making the R light beam passthrough to enter projection optics 4 such as e.g. a zoom lens afterhaving been reflected by a dichroic mirror 27 having a function ofreflecting the R light beam and the B light beam. On the other hand theG light beam and the B light beam reflected by the R transmissiondichroic mirror 24 enters a B reflection dichroic mirror 25. The B lightbeam is reflected by the mirror passes through a condenser lens 7B andan incident side polarizer 20B to enter liquid crystal display elements3B and passes through an exit side polarizer 21B and a field lens 8Bdisposed on the light exit side of the liquid crystal display elements3B. The B light beam exiting from the field lens 8B is reflected by thedichroic mirror 26 having a function of reflecting the B light beam toenter the projection optics 4 after having been reflected by thedichroic mirror 27 together with the R light beam.

On the other hand, the G light beam, which has passed through a dichroicmirror 25, passes through a condenser lens 7G and an incident sidepolarizer 20G to enter liquid crystal display elements 3G and passesthrough an exit side polarizer 21G and a field lens 8G disposed on thelight exit side of the liquid crystal display elements 3G.

The G light beam exiting from the field lens 8G is reflected by areflective mirror 28 to enter the projection optics 28 after having beentransmitted by the dichroic mirror 27 together with the R light beam andthe B light beam. In this way, the light beams corresponding to R, G andB are separated and combined by color separation optics and colorcombination optics and the projection optics 4 enlarge an image on theliquid crystal display elements corresponding to R, G and B to obtain areal image by combining and enlarging the images of the different colorson a screen. In FIG. 7, 30 is a housing; 31 is a speaker; 32 is a powers upply circuit; and 43 is an image signal circuit. Further 33 is ablowoff duct having a function of conducting wind from a case 19, etc.for the illumination optics 2 to a blowoff fan 34. Further the speaker31 gives users voice information parallelly to image information.

The size of the whole device is decreased and the shape thereof isrectangular by arranging the illumination optics 2 and the projectionoptics 4 so that optical axes thereof are parallel to each other andfurther by arranging the power supply circuit 32 and the image signalcircuit 42 through a color separation and combination unit 44 consistingof the color separation optics, the liquid crystal display elements andthe color combination optics, as indicated in the figure. In this way itis possible to obtain a shape suitable for a utilization mode in ameeting room, etc., in which a shorter side of the rectangle is facingthe screen side.

The lamp 10 in the present embodiment is a metal halide lamp asindicated e.g. in FIG. 3. The functions of the illumination opticsincluding the lamp are as described previously and explanation thereofis omitted here.

A transmission type liquid crystal panel of p−SiTFT e.g. of class, wherethe diagonal of the image screen is 1 inch long, is used for the liquidcrystal display elements 3 in the present embodiment in order to realizethe down-sizing of the whole device. For the liquid crystal displayelements, e.g. 3R, there are disposed the incident side polarizer 20R,which is a polarizer transmitting linearly polarized light, and the exitside polarizer 21R, which is a polarizer transmitting linearly polarizedlight having a polarization plane, rotated by 90° with respect to theincident side polarizer 20R. Image information is displayed bycontrolling the transmitted amount of incident light while combining thefunction of rotating the polarization plane by the electro-opticaleffect of liquid crystal in the liquid crystal display elements 3R withthe function of selecting a polarization component of the incident sidepolarizer 20R and the exit side polarizer 21R serving as polarizers. Itcan be said that this is identical for B and R.

19 in FIG. 7 represents a case for the illumination optics 2. In casewhere any satisfactory image quality performance such as brightness,etc. as a display device can be obtained no more because of an expiredlife time of the lamp, the lamp can be exchanged by exchanging the case19 whole. A concrete example of display means having such a constructionwill be explained, referring to FIG. 8.

FIG. 8 is a cross-sectional view showing the construction of a concreteexample of display means applied to the projection type liquid crystaldisplay device according to the present invention.

The example indicated in FIG. 8 is so constructed that the ellipticmirror 5 and the spherical mirror 6 are arranged, through a holdingreflective mirror plate 36. In this way the elliptic mirror 5 and thespherical mirror 6 can be located precisely. Particularly, in case wheresmall size liquid crystal display elements are used, and further in casewhere the light utilization efficiency is high, since positionalprecision for the elliptic mirror 5 and the spherical mirror 6, etc. issevere, it is efficient to arrange them through a member. Further theexample indicated in FIG. 8 is so constructed that the holding plate 36is put between other members 35 and 37 and in this way mounting work atfabrication can be effected easily.

In the construction according to the present invention it is useful forincreasing in brightness uniformity over the whole screen, lightutilization efficiency, etc. to have either one or a plurality of theelliptic mirror 5, the spherical mirror 6, the first lens array 22, thesecond lens array 23, the condenser lens 7 and the field lens 8 have ashape varied at the peripheral portion with respect to the portion nearthe optical axis. For example, in case where the central portion nearthe optical axis of the condenser lens 7 has a not spherical shape closeto a plane, as indicated in FIG. 9, the ratio of the brightness at theperipheral portion to the brightness at the central portion can beincreased further, which improves brightness uniformity over the wholescreen.

As described above, according to the present invention, it is possibleto increase utilization efficiency of the light emitted by the lightsource and thus to realize a bright projection type liquid crystaldisplay device having a small size and a good image quality performance.

What is claimed is:
 1. A projection type liquid crystal display devicecomprising: a light source; illumination optics having a function ofirradiating a plane to be irradiated with light emitted by said lightsource; liquid crystal display elements modulating light; and projectionoptics for projecting light exiting from said liquid crystal displayelements; wherein said illumination optics include at least an ellipticmirror and a spherical mirror, and said illumination optics includefurther a first lens array and a second lens array, in which a pluralityof lenses are arranged perpendicularly to an optical axis, from thelight source side; and a condenser lens for irradiating said liquidcrystal display elements with light after exit from said second lensarray with a high efficiency, and wherein said lenses constituting saidfirst lens array disposed on the light source side in said illuminationoptics are rectangular and at least one lens thereof has an opticalaxis, which is not at the center of a rectangular shape.
 2. A projectiontype liquid crystal display device comprising: a light source;illumination optics having a function of irradiating a plane to beirradiated with light emitted by said light source; liquid crystaldisplay elements modulating light; and projection optics for projectinglight exiting from said liquid crystal display elements; wherein saidillumination optics include at least an elliptic mirror and a sphericalmirror, and said illumination optics include further a first lens arrayand a second lens array, in which a plurality of lenses are arrangedperpendicularly to an optical axis, from the light source side; and acondenser lens for irradiating said liquid crystal display elements withlight after exit from said second lens array with a high efficiency, andwherein at least one of said lenses constituting said second lens arraydisposed on the side of said liquid crystal display elements in saidillumination optics are rectangular and at least one lens thereof has anoptical axis, which is not at the center of a rectangular shape.
 3. Aprojection type liquid crystal display device comprising: a lightsource; illumination optics having a function of irradiating a plane tobe irradiated with light emitted by said light source; liquid crystaldisplay elements modulating light; and projection optics for projectinglight exiting from said liquid crystal display elements; wherein saidillumination optics include at least an elliptic mirror and a sphericalmirror, and said illumination optics include further a first lens arrayand a second lens array, in which a plurality of lenses are arrangedperpendicularly to an optical axis, from the light source side; and acondenser lens for irradiating said liquid crystal display elements withlight after exit from said second lens array with a high efficiency,wherein said condenser lens has non-spherical shape close to a plane ata central portion close to an optical axis.
 4. A projection type liquidcrystal display device according to claim 3, wherein at least one isquadrilateral and at least one is pentagonal among said lensesconstituting said second lens array.
 5. A projection type liquid crystaldisplay device including a light source, illumination optics thatirradiate a plane with light emitted by the light source, liquid crystaldisplay elements which modulate the light, and projection optics thatproject the light exiting from the liquid crystal display elements,wherein: the illumination optics provide at least one ellipse mirror, afirst lens array having a plurality of lenses disposed perpendicularlyon an optical axis from the light source side, a second lens array, anda condenser lens for irradiating the liquid crystal display elementswith the light after exiting from the second lens array with a highefficiency; each of the lenses constituting the first lens arraydisposed on the light source side of the illumination optics has arectangular shape; and at least one lens of which an optical axis is notpresent on a center of the rectangular shape is provided.
 6. Aprojection type liquid crystal display device according to claim 5wherein the illumination optics has at least one spherical mirror.
 7. Aprojection type liquid crystal display device including a light source,illumination optics which irradiate a plane with light emitted by thelight source, liquid crystal display elements which modulate the lightemitted by the light source, projection optics which project the lightexiting from the liquid crystal display elements, wherein: theillumination optics provide at least one ellipse mirror, one sphericalmirror, a first lens array having a plurality of lenses disposedperpendicularly on an optical axis from the light source side, a secondlens array, a condenser lens for irradiating the liquid crystal displayelements with the light after exiting from the second lends array with ahigh efficiency; wherein each of the lenses of the second lens array hasa rectangular shape; and the optical axis of the lens is not positionedon center of the rectangular shape.
 8. A projection type liquid crystaldisplay device according to claim 7 wherein the illumination optics hasat least one spherical mirror.
 9. A projection type liquid crystaldisplay device including a light source, illumination optics whichirradiate a plane with light emitted by the light source, liquid crystaldisplay elements which modulate the light, and projection optics whichproject the light exiting from the liquid crystal display elements,wherein: the illumination optics have at least one ellipse mirror andone spherical mirror; and the light source has a light emitting bulbwith a reflective layer applied, wherein the reflective layer reflectslight emitted from a lighting point of the light source, which is notdirectly incident on the spherical mirror, onto the spherical mirror.10. A projection type liquid crystal display device according to claim 9wherein a reflection surface of the spherical mirror is formed of areflection film for also reflecting a light present out of visible lightrange.
 11. A projection type liquid crystal display device according toclaim 10 wherein the reflection surface of said spherical mirrorincludes a reflective film formed by an aluminum evaporation.
 12. Aprojection type liquid crystal display device including a light source,illumination optics which irradiate a plane with light emitted by thelight source, liquid crystal display elements which modulate the light,projection optics which project the light exiting from the liquidcrystal display elements, wherein: a lens constituting a lens arrayprovided between the illumination optics and the liquid crystal displayelements includes a lens having at least one rectangular shape, a lenshaving at least one quadrilateral shape and a lens having at least onepentagonal shape.
 13. A projection type liquid crystal display deviceincluding a light source, irradiation means for irradiating an emittedlight from the light source on a place to be irradiated, a liquidcrystal display elements for modulating the light, and projection meansfor projecting the emitted light from the liquid crystal displayelements, wherein said irradiation means includes at least an ellipticmirror and a spherical mirror, irradiating the light from saidirradiation means on a lens array in which optical axes of lenses ofsaid lens array deviate from respective centers of said lenses.
 14. Aprojection type liquid crystal display device according to claim 13,wherein at least one of said lenses of said lens array is of arectangular form.
 15. A projection type liquid crystal display deviceaccording to claim 13, wherein said lenses of said lens array include atleast one lens having a quadrilateral form and at least one lens havinga pentagonal form.